I developed a small driver to connect my hubitat with wazo-platform, Wazo is an opensource programmable telecommunication platform.
The source code is on github on sboily/hubitat-wazo.
I'm using a websocket and REST API, it's not yet finish, but good sample for people want to have a websocket exemple with hubitat.
Do you know if there is a better documentation to develop on hubitat, the doc is not really usefull ... There is some informations who i don't know what it can do exactly.